In order to deliver qualified results from the analysis work, the data allocation and modelling were the key prerequisites for the power system simulations within the study. In this respect, the obligations of both sides for the provision of data and models were stipulated in the Cooperation Agreement signed by the UCTE and the IPS/UPS: It was a common understanding that the quality of the simulation results truly depended on the quality of the input data. Therefore, providing the necessary data and information was a sine qua non condition for the successful completion of this comprehensive study.